Just found that the news of Hyun Joong being in the Korean version of Mischievous kiss announced in the comic author’s page
Tada Kaoru is the author of the original comic
She is already aware of the Korean version casting and been updated about this in her own hp ^^
Her Japanese hp address is http://tadakaoru.jp/top.html
English Translation: SS501fighting.wordpress.com
Do not re-edit+HOTLINK
Please repost with full credit... kamsahamnida!